Auxin Regulates Sucrose Transport to Repress Petal Abscission in Rose (Rosa hybrida) [
Auxin Regulates Sucrose Transport to Repress Petal Abscission in Rose (Rosa hybrida) [
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生长素调节蔗糖转运抑制玫瑰花瓣脱落 [
DOI：
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发表时间：
2020
期刊：
影响因子：
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通讯作者：
Junping Gao
中科院分区：
文献类型：
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作者：
Yue Liang;Chuyan Jiang;Yang Liu;Yuerong Gao;Jingyun lu;Palinuer Aiwaili;Zhangjun Fei;Cai-Zhong Jiang;Bo Hong;Chao Ma;Junping Gao
植物的发育转变需要足够的碳资源，并且由于对碳水化合物/同化物的竞争而经常发生器官分解。生理学研究表明，器官脱落可能被激活的Suc剥夺，然而，一个潜在的监管机制，联系Suc运输器官脱落尚未确定。在这里，我们报告说，运输Suc和植物激素生长素花瓣通过韧皮部的分离区（AZ）减少在玫瑰（玫瑰杂交）花瓣分离过程中，生长素调节Suc运输到花瓣。在玫瑰花瓣脱落过程中，AZ中Suc转运蛋白RhSUC 2的表达下降。类似地，RhSUC 2的沉默降低了花瓣中的Suc含量并促进花瓣脱落。我们确定生长素信号蛋白RhARF 7与RhSUC 2的启动子结合，并且RhARF 7的沉默降低花瓣Suc含量并促进花瓣脱落。RhSUC 2在花瓣AZ中的过表达恢复了由RhARF 7沉默引起的加速花瓣脱落。此外，用生长素和Suc处理玫瑰花瓣延迟乙烯诱导的花瓣脱落，而RhARF 7和RhSUC 2的沉默加速乙烯诱导的花瓣脱落。我们的研究结果表明，生长素调节Suc运输过程中花瓣脱落，这一过程是由一个RhARF 7-RhSUC 2模块在AZ。
Developmental transitions in plants require adequate carbon resources, and organ abscission often occurs due to competition for carbohydrates/assimilates. Physiological studies have indicated that organ abscission may be activated by Suc deprivation; however, an underlying regulatory mechanism that links Suc transport to organ shedding has yet to be identified. Here, we report that transport of Suc and the phytohormone auxin to petals through the phloem of the abscission zone (AZ) decreases during petal abscission in rose (Rosa hybrida), and that auxin regulates Suc transport into the petals. Expression of the Suc transporter RhSUC2 decreased in the AZ during rose petal abscission. Similarly, silencing of RhSUC2 reduced the Suc content in the petals and promotes petal abscission. We established that the auxin signaling protein RhARF7 binds to the promoter of RhSUC2, and that silencing of RhARF7 reduces petal Suc contents and promotes petal abscission. Overexpression of RhSUC2 in the petal AZ restored accelerated petal abscission caused by RhARF7 silencing. Moreover,.treatment of rose petals with auxin and Suc delayed ethylene-induced abscission, whereas silencing of RhARF7 and RhSUC2 accelerated ethylene-induced petal abscission. Our results demonstrate that auxin modulates Suc transport during petal abscission, and that this process is regulated by a RhARF7-RhSUC2 module in the AZ.